I wasn't smart enough to know those things when I took my Mormon lessons. I went through three sets of missionaries during high school. And when I told them I wasn't getting an answer, they all said, "just keep praying." Eventually I reached a point where I realized it was a waste of time, and that the Mormon religion was not the true religion. And in the 30 years since, everything I've read has convinced me I was correct. (Of course, I'm not 100% certain. I could be wrong. And extraordinary evidence could change my mind). But it is amazing that all Mormons claim ("testify") they had this feeling themselves, and they know their religion is the true one.
That's a dangerous belief. See "Under the Banner of Heaven" by Jon Krakauer. Just 20 years ago, here in America a small group of men believed that killing people who didn't agree with them was carrying out God's plan.
One of the most important things I know now, but didn't know then, is that they, and all other people who prosthlytize (sp) their religious beliefs, are not interested in a rational examination of their religion. They are like salesmen - they want to sell you their religion - and will not admit evidence against it. They will tell you why their religion is the correct one, and why other religions are incorrect, but they are not going to take time to look at the evidence against their religion, or the evidence against God. They will tell you what to read, but they won't read the books that you ask them to. Therefore the discussions are one-sided. They aren't spending time with you to discuss religion - they are there to convert you to believe what they believe.
There are books, and now websites, devoted to exposing the history and changing beliefs of the Mormons, Jehovah's Witnesses, Scientologists (a cult), Muslims, and belief in God. Their are many books and websites devoted to exposing the contradictions in the Bible. Use them. Read them. Educate yourself, before accepting what religious salesmen tell you. Remember, if it doesn't help them sell their product, they won't mention it.